Stress tolerance and virulence of insect-pathogenic fungi are determined by environmental conditions during conidial formation

Autor(es)

Rangel, Drauzio E. N. ^{[1, 2]} ; Braga, Gilberto U. L. ^[3] ; Fernandes, Everton K. K. ^{[1, 4]} ; Keyser, Chad A. ^[5] ; Hallsworth, John E. ^[6] ; Roberts, Donald W. ^[1]

Afiliação do(s) autor(es)

^[1] Utah State Univ, Dept Biol, Logan, UT 84322 - USA

^[2] Univ Vale Paraiba, Inst Pesquisa & Desenvolvimento, BR-12244000 Sao Jose Dos Campos, SP - Brazil

^[3] Univ Sao Paulo, Fac Ciencias Farmaceut Ribeirao Preto, BR-14040903 Ribeirao Preto, SP - Brazil

^[4] Univ Fed Goias, Inst Patol Trop & Saude Publ, BR-74605050 Goiania, Go - Brazil

^[5] Univ Copenhagen, Dept Plant & Environm Sci, DK-1871 Frederiksberg - Denmark

^[6] Queens Univ Belfast, Inst Global Food Secur, Sch Biol Sci, MBC, Belfast BT9 7BL, Antrim - North Ireland

• Tipo de documento: Artigo Científico
• Fonte: CURRENT GENETICS; v. 61, n. 3, p. 383-404, AUG 2015.
• Citações Web of Science: 62

Resumo

The virulence to insects and tolerance to heat and UV-B radiation of conidia of entomopathogenic fungi are greatly influenced by physical, chemical, and nutritional conditions during mycelial growth. This is evidenced, for example, by the stress phenotypes of Metarhizium robertsii produced on various substrates. Conidia from minimal medium (Czapek's medium without sucrose), complex medium, and insect (Lepidoptera and Coleoptera) cadavers had high, moderate, and poor tolerance to UV-B radiation, respectively. Furthermore, conidia from minimal medium germinated faster and had increased heat tolerance and were more virulent to insects than those from complex medium. Low water-activity or alkaline culture conditions also resulted in production of conidia with high tolerance to heat or UV-B radiation. Conidia produced on complex media exhibited lower stress tolerance, whereas those from complex media supplemented with NaCl or KCl (to reduce water activity) were more tolerant to heat and UV-B than those from the unmodified complex medium. Osmotic and nutritive stresses resulted in production of conidia with a robust stress phenotype, but also were associated with low conidial yield. Physical conditions such as growth under illumination, hypoxic conditions, and heat shock before conidial production also induced both higher UV-B and heat tolerance; but conidial production was not decreased. In conclusion, physical and chemical parameters, as well as nutrition source, can induce great variability in conidial tolerance to stress for entomopathogenic fungi. Implications are discussed in relation to the ecology of entomopathogenic fungi in the field, and to their use for biological control. This review will cover recent technologies on improving stress tolerance of entomopathogenic fungi for biological control of insects. (AU)

• Processo FAPESP: 14/01229-4 - International Symposium on Fungal Stress - ISFUS
• Beneficiário: Drauzio Eduardo Naretto Rangel
• Modalidade de apoio: Auxílio Organização - Reunião Científica
• Processo FAPESP: 12/15204-8 - Estudo mecanístico da inativação fotodinâmica de fungos patógenos de humanos e de fungos fitopatógenos
• Beneficiário: Gilberto Úbida Leite Braga
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 10/06374-1 - Luz visível durante o crescimento induz aumento de tolerância de conídios a diferentes condições de estresse em fungos
• Beneficiário: Drauzio Eduardo Naretto Rangel
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores
• Processo FAPESP: 13/50518-6 - Genes relacionados com estresse são induzidos pela luz visível durante o crescimento micelial, resultando em aumento da tolerância de conídios a condições de estresse
• Beneficiário: Drauzio Eduardo Naretto Rangel
• Modalidade de apoio: Auxílio à Pesquisa - Regular